[0001] The present invention relates to an improved device for injecting a medicament to
be used by diabetes patients, or other patients that self-medicate injectable drugs.
BACKGROUND OF THE INVENTION
[0002] Diabetes patients that inject insulin have to check their blood glucose value and
carry out insulin injections, sometimes several times every day. They also need to
log their blood glucose values and register the amount of insulin that has been injected
in order to monitor the disease. Today this requires several different devices: means
for testing blood glucose including means for taking a blood sample (such as a lancet),
disposable test strips and a blood glucose meter; an insulin injection device, extra
insulin cartridges, replacement needles and also a log book and writing utensils for
registering blood glucose values and injections. The diabetic patient has to carry
all these items with him or her, which is not only a hassle but also a risk for the
patient, since losing equipment puts him or her at danger, since proper treatment
is then perhaps not achieved.
[0003] The amount of insulin that the patients injects is based on the blood glucose measurements.
Injection of an incorrect amount of insulin is dangerous to the patient. Therefore,
it is important that this procedure is carried out in a correct and safe manner.
[0004] Furthermore, since it is very important that the patient actually treats him or herself
it is desirable that self-medication causes minimal inconvenience for the patient
and affect the patient's life style as little as possible.
[0005] In order to solve this problem there has been developed devices that integrates all
these functionalities, for example
WO2009027950 which describes a portable medical device that integrates blood glucose measurement
and insulin injection. It has a lancet for obtaining a blood sample. The lancet, and
the injections means are placed on the same end of an elongated housing in order to
avoid blood splashing getting in touch with mechanical movable parts and/or electronic
parts inside the housing.
[0006] The site http://www.brightercompany.com/product-information as visited on November
6
th, 2013 has a film that discloses a medical device. It has a test strip port located
adjacent and such that the test strip is parallel to the injection needle. It has
one display that shows both blood glucose concentration and the amount of insulin
to be injected by the device.
[0007] The diabetes patient is used to carry out the different steps of blood glucose measurement
and insulin injection in a certain order and in a certain manner. This contributes
to that the patient carries out the procedure in a safe manner. This is particularly
important since the cognitive abilities of diabetes patients may sometimes be compromised
due to fluctuating blood glucose levels.
[0008] There is also a need for improved logging of injections. Currently registration of
blood glucose measurement is usually carried out manually by the patient. Manual registrations
are prone to human errors, for example the patient may forget to register a value
or enters the wrong value. Automatic logs have been proposed, for example in
WO2012068214.
[0009] Before each injection it is important that the user primes the injection needle,
in order to ensure that there are no air bubbles and no clogs in the needle. This
is carried out by ejecting a small amount of medication from the needle. A disadvantage
with current automatic logs is that they cannot distinguish between injection events
and priming events.
WO 2009083600 proposes a medical device that can log insulin injections and distinguish between
injections events and priming events depending on the speed of the ejected liquid
during ejection. However, that invention assumes that the ejection speed is controlled
by the device. In devices where the injection speed varies, for example because the
user pushes a plunger with different speed from time to time, such a solution cannot
be used.
[0010] WO2010098927 discloses a device that can distinguish between real injections and priming events
by using a gravity or inertial sensor. However, the proposed device is based on the
assumption that injection does not take place upwards. This is not always true.
[0011] Thus, there is a need for improved log that can distinguish between injection events
and priming events in safe and convenient manner.
SUMMARY OF THE INVENTION
[0012] The invention is defined by the subject-matter of claim 1. Further embodiments are
defined in the dependent claims.
[0013] There is provided a portable medical device for injecting a medicament comprising
means for injecting a medicament in a patient, means for automatically recording the
amount of medicament that is injected at a certain time point as an ejection event,
and a proximity sensor that can sense the proximity of a solid object in the same
direction as an injection needle when the needle is attached to the device, where
the medical device s configured to tag the ejection event as an injection event if
the injection takes place in the proximity of a solid object, and tagging the ejection
event as a priming ejection if the ejection does not take place in the vicinity of
a solid object characterized in that said proximity sensor is able to detect the proximity
of the solid object without making contact with the solid object.
[0014] The sensor is suitable an infrared sensor. The device may be configured to tag ejections
as injections when the distance from the front plate of the cartridge housing to an
object is less than a threshold value T that is described in more detail below. The
threshold value can be 200 mm.
[0015] In an alternative embodiment where an ejection event is tagged as an injection event
if, when insulin is ejected, the distance from the sensor to the tip of the needle
(D
1) is larger than the distance from the sensor to a solid object (D
2) and where D
1-D
2≥ 0.1 mm.
[0016] The device can be used for logging events in electronic log that can be conveniently
accessed by the user through a user interface on the device. The electronic log is
an improvement of current logs that cannot distinguish between real injections and
priming ejections. Thus, the user is provided with a reliable log for injections and
glucose measurements which improves safety.
[0017] In one embodiment, which is not according to the invention, the method is such that
information about the injection events are accessible to the user thought a user interface
on the medical device and information about the priming events are not accessible
to the user via a user interface on the medical device. The priming events are only
accessible, for example through a data port, or after entering a code. Thus, the priming
events are not visible to the user. This has the advantage that the user does not
confuse the priming events with real injections in the log. However, the priming events
are still accessible for doctors and nurses and persons that carry out service on
the device.
[0018] In one embodiment the device is configured to allowing a user, using a user interface
to tag an injection event with additional information regarding one selected from
the group consisting of a blood glucose measurement, health status, taking a meal
and exercise.
[0019] In one embodiment the device is configured to automatically tagging an injection
event with a blood glucose measurement if the blood glucose measurement has been made
within 30 min of the time point of the injection event.
[0020] Blood glucose measurements are affected by insulin injections, meals, exercise and
illness. The advantage of this arrangement is that, when the user reviews blood glucose
measurements, he or she can take meals, etc. into account in a convenient manner.
The advantage with automatic tagging is that tagging occurs even if the user forgets
to tag.
DEFINITIONS
[0021] As used herein, "user" and "patient" refers to the person that uses the device to
test blood glucose and inject himself or herself with insulin.
[0022] Although it is frequently referred to insulin in this application, the inventions
disclosed herein may be useful for devices for injecting other medicaments that are
self-administered by the patient, such as, for example growth hormone.
[0023] "Insulin" covers not only insulin in its natural form but also insulin variants and
analogs that are administered to diabetic patients.
[0024] "Tagging" means storing additional information about a database entry in a database.
[0025] "Ejection" means expulsion of a liquid medicament from a medical device with injection
means, for example by a plunger creating a pressure. Typically, ejection is carried
out from the tip of an injection needle which can be attached to the device.
[0026] "Injection" is ejection where the liquid medicament, after being ejected, enters
into a solid object (typically the body of a patient).
[0027] "Priming" is ejection where ejection does not take place into a solid object. For
example, the liquid medicament may be sprayed into the air, or drip from the tip of
the needle.
[0028] When it is referred to "date and time" or similar herein, it is meant a fixed time
point. A fixed time point does not necessarily have to be expressed as date and time.
BRIEF DESCRIPTION OF DRAWINGS
[0029]
FIG. 1 is a schematic overview of the interior of a medical device.
FIG. 2-3 are schematic overviews of an injection needle and an insulin cartridge.
FIG. 4-5 shows examples of the exterior of the device.
FIG. 6 shows an example of arrangement of sensors.
FIG. 7-9 are examples of an arrangement of the second display, where FIG. 7 shows
the interior of a medical device and FIGs 8-9 shows the exterior.
FIG. 10 is a schematic overview of the connection of a sensor to a processing unit.
FIG. 11-13 show examples of arrangement of first and second displays and other features
of the device.
FIG. 14 shows the threshold distance for a proximity sensor in the device.
FIG. 15 is a flowchart showing a method for logging insulin ejection events.
FIG. 16 is a schematic overview of an example of database.
FIG. 17 shows various connections to a processing unit.
FIG. 18-19 are flowcharts that show examples of logging of blood glucose measurements
and ejection events.
FIG. 20-22 show how a proximity sensor can be used for classifying ejection events.
FIG. 23-24 shows examples of an electronic display in a switched-off state.
FIG. 25-27 shows details of an example of a drive mechanism of injection means.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0030] FIG. 1 is a general schematic overview of the medical device 1, which in a preferred
embodiment comprises injection means comprising a cartridge housing 10. The cartridge
40 is placed by the user in the cartridge housing 10 of the device 1. Injection of
insulin is carried out with a needle 42 the needle hub 44 of which is attached to
the top 43 of cartridge 40 by the user as shown in FIGs 2 and 3. The cartridge 40
and the needle 42 are usually supplied separately from the device 1 and does not form
a part of this invention. Returning to FIG 1, the injection means further comprises
a drive mechanism 13 that causes the ejection of insulin through the needle 42 and
means for setting the amount of insulin to be injected 5 (dose setting means).
[0031] The drive mechanism 13 can comprise a plunger 41 that causes the ejection of medicament
through the needle 42 when it travels in the longitudinal direction of the cartridge
housing. The plunger 41 may be adapted push on a second plunger 45 supplied in the
cartridge 40. The front of the main part of the cartridge 40 can rest against the
front plate 4 of the cartridge housing 10 as shown in FIG 14 (note that the needle
points in the opposite directions in FIG 1 and FIG 14).
[0032] Suitably the device 1 also comprises a blood glucose meter 9.
[0033] Preferably the device 1 is portable. Then the user can easily bring the device with
him or her.
[0034] A preferred design of the device 1 comprises a housing 7 which is a hollow body that
contains the various parts of the device 1. Preferably the housing 7 is of a size
and shape that enables the user to rest the device in the hand. The housing may have
one or more detachable parts that serves as cover 8, for example as cover for the
injection needle. The housing can be made of plastic or metal, where plastic is a
preferred material. The drive mechanism 13 is preferably enclosed in the housing 7,
as is processing unit 19 and glucose meter 9.
[0035] Typically, the device 1 is used in the following manner. First the user uses the
lancet 22 to puncture the skin in order to obtain a drop of blood. The drop is then
brought in contact with the end of a test strip. The other end of the test strip is
entered into blood glucose meter 9 through the test strip port 2. The blood glucose
meter 9 then carries out measurement of the glucose content of the blood and presents
a blood glucose concretion value to the user on a display 3. Based on this value,
the user decides how much insulin that is to be injected. The user then sets the amount
of insulin with the dose setting means 5 and injects himself/herself.
[0036] The device 1 has a user interface with at least one display. The display can show
various kinds of information, such as blood glucose measurements, injection events,
date and time. The device 1 has injection means, including a display that shows the
amount of insulin to be injected and a drive mechanism 13 that preferably is powered
by the user (user-powered). Such injection means has proven to be very reliable, as
they require no electricity and the drive mechanisms can be made very durable. Examples
of user-powered drive mechanism for injecting insulin includes mechanisms that are
powered by the user pressing an injection actuator. The pressing power is mechanically
transferred to the plunger 41. Examples of user-powered drive mechanism are known
in the art, examples include
US 5,593,390,
US 6,221,046,
US 5,279,586 and
WO2009027950. A user-powered drive mechanism may suitably have a mechanical display. These require
no electricity and are very reliable.
[0037] However, it is also desirable that the device 1 has a display that is small, light
and that can show a variety of symbols and letters and that can be easily connected
to a microprocessor. Therefore, in a preferred embodiment, the device 1 has two displays;
a first display 3 which is non-mechanical, preferably an electronic display such as
an OLED, a PDP or an LCD display, and a second display 6 which is mechanical and which
shows the dose setting.
[0038] FIG 4 shows an example of the exterior of the device 1. In the housing 7 is mounted
first display 3. The second display 6 and dose setting means 5 are also visible. A
part of the housing 7 forms a removable cap 8 that protects the injection needle.
Thus, when the cap 8 is on, the needle 42 is inside the housing 7.
[0039] FIG 5 shows essentially the same as FIG 5, as it shows the housing 7 of the device
1 with the cap 8 removed to expose the cartridge housing 10, needle 42 (with an additional
protective cap). First display 3, second display 6 and dose setting means 5 are also
visible.
[0040] The medical device 1 will now be described in more detail with reference to FIG 1.
Preferably the device 1 is equipped with a blood glucose meter 9 as shown in FIG 1.
Blood glucose meters are well known in the art. Usually blood glucose measurement
is carried out with disposable test strips 28 as is well known in the art. The test
strip 28 may be of the kind that contains one or more chemicals that react with glucose
in the blood in such a way that the blood glucose concentration can be measured. For
example, the test strip is a standard glucose oxidase/ferrocyanide test strip where
the glucose concentration affects an electric current in a way that can be converted
to a blood glucose concentration measurement.
[0041] Suitably, blood glucose measurement by glucose meter 9 is automatically started when
a test strip 28 is inserted into the test strip port 2. For example, a sensor senses
when a test strip is introduced into the test strip port 2. An example of how test
strip 28 is inserted into test strip port is shown in FIG 13. The user then produces
a drop of blood, preferably by using the lancet 22 as described below. The user then
touches a drop of blood to the edge of the test strip which absorbs the blood and
delivers it by capillary action along the test strip 28 to the site where the chemical
reaction occurs. Typically, a blood drop with a volume of 1-20 microliters is used.
[0042] By means of the integrated blood glucose meter 9 the glucose concentration is determined
and indicated on the first display 3 within a few seconds, to allow the user to go
to the injection mode and adjust the amount of insulin to be injected. Blood glucose
measurements are usually expressed as mmol/L or mg/L and the device can suitably show
the blood glucose concentration in one of these units. Preferably the user primes
the injection means before setting the amount of insulin to be injected.
[0043] The means for injecting insulin comprises a cartridge housing 10 for inserting a
cartridge 40 pre-loaded with insulin. The cartridge housing 10 is adapted to receive
an insulin cartridge 40. The cartridge housing 10 has at least a front plate 4 that
limits the movement of the insulin cartridge 40 in the direction of injection. The
needle 42 in FIG 2 and FIG 3 can be snapped on or screwed onto the top of the cartridge
40 or connected to cartridge 40 with a luer lock or connected by other suitable means.
The cartridge 40 can be replaced in a simple manner by the user.
[0044] The injection means comprises a drive mechanism 13 which causes the plunger 41 to
move when the user interacts with the device to cause ejection of insulin, for example
by pressing actuator 12. The drive mechanism 13 can be carried out in different manners
as long as it is suitable to inject insulin from an insulin cartridge 10 in a patient
and can be combined with sensors as described below.
[0045] The means for injecting insulin comprises means 5 for setting the amount of insulin
to be ejected by the device (dose setting means). The dose setting means 5 can be
a rotatable dosing knob 5, but it can be any type of means by which the user can instruct
the drive mechanism 13 of the injection means of device 1 to change its dose setting.
For example, it may be a plus/minus buttons or a lever. The rotatable dosing knob
suitably has grooves for enhancing the grip. The amount of insulin to be ejected by
the device 1 is shown on a display 6, referred to as the second display 6, which is
described in more detail below. The dose setting means 5 is connected to, and may
form a part of the drive mechanism 13. The drive mechanism 13 can cause the plunger
41 to be displaced thus creating a pressure in insulin cartridge 40 in the cartridge
housing 10 by pressing on second plunger 45 in the cartridge 40. The pressure causes
ejection of insulin trough the needle 42 connected to the cartridge 40. The drive
mechanism 13 can cause the plunger 41 to be displaced to in a variable manner. The
setting of the dose setting means 5 determines how far the drive mechanism 13 displaces
plunger 41 during ejection.
[0046] The dose setting means 5 should have at least one setting that does not allow the
ejection of insulin. When the dose setting means 5 is in this position no insulin
is ejected when the user instructs the device to eject insulin, for example when the
user applies pressure to the actuator 12. Thus, the plunger 41 does not move when
the user presses the actuator 12 when the dose setting means 5 is in this position.
[0047] The dose setting means 5 should have at least one setting that allows the ejection
of insulin from the cartridge, for example a fixed amount of insulin. Typically, the
settings for the second display 6 are 0, 1.0, 1.5, 2.0, 2.5 and so on representing
insulin units, where one unit may represent 0.01 ml of medicament. The "0" setting
is a setting that does not allow ejection of insulin. The settings 1.0, 1.5, 2.0,
and 2.5 are settings that allow the ejection of insulin.
[0048] The means for injecting insulin also comprises an injection actuator 12. This may
be in the form of knob that is pressed by the user. The dosing knob and the injection
actuator may be integrated in the same unit such that the rotatable dosing knob 5,
12 can be depressed, and when it is depressed ejection takes place.
[0049] The drive mechanism 13 for ejecting insulin can be an electric pump. Preferably,
however, it is a user-powered drive mechanism. Examples of user powered mechanical
drive mechanism and dose setting means and mechanical displays are disclosed in
US 5,593,390,
US 6,221,046,
US5279586 and
WO2009027950.
[0050] The drive mechanism 13 can be powered by the user such that when the user uses the
actuation means 12 the power is transferred to the drive mechanism 13. The amount
of insulin to be ejected is set by turning the dose setting means 5 so that mechanism
13 can move plunger 41 to eject insulin from cartridge 40 and the dose setting means
5 determines how far the plunger 41 travels.
[0051] An example of a user powered drive mechanism and a mechanical display is shown in
FIG. 25. The mechanism is shown when set in a position that does not allow injection
of insulin. Sleeve 14 serves to display the dose setting digits to the user and to
interact with switch 18 as described below. Sleeve 14 has dose settings marked on
the outside. These marking is visible to the user, for example through a window as
seen in FIG 7. Sleeve 14 can rotate with turning of dose setting means 5. When a user
rotates dose setting means 5 to set the dose, sleeve 14 rotates with it. Sleeve 14
then moves to the right in the figure due to threading 57. Nut 52 rotates together
with sleeve 14 by means of cone clutch 53. This makes the nut 52 go to the right in
the figure. The movement of nut 52 from its left-most position sets the injection
means to a setting that allows the injection of insulin.
[0052] When the user has set the dose he or she is not ready to eject insulin. The injection
actuator 12 is connected at the end of the sleeve 14. The injection actuator 12 can
be pressed by the user. The arrow in FIG 25 indicates direction of pressing. Upon
pressing the injection actuator 12 then moves to the left in the figure. The outer
surface of injection actuator 12 is covered with a material (for example rubber) that
causes high friction between the finger of the user and the injection actuator 12.
When the user presses the injection actuator 12, the nut 52 is released from sleeve
14 by cone clutch 53 and moves to the left to the same extent that the injection actuator
12 is pressed. Injection actuator 12 then, subsequently, presses on sleeve 14 which
turns with aid of threading 57 and moves to the left. Release of cone clutch 53 is
achieved by gap 58. Gap 58 causes injection actuator 12 to first press on nut 52 and
then, after being presses slightly more, on sleeve 14, causing cone clutch 53 to be
released. Nut 52 is not allowed to turn when pressed by injection actuator 12 because
of the high friction between the finger of the user and the outer surface of injection
actuator 12 and because the cone clutch 53 is released. Nut 52, however, moves to
the left when injection actuator 12 is pressed. This movement continues until the
right end (in the figure) of the turning part 27 has reached the inner surface 56
of the injection actuator 12. This movement of nut 52 causes turning part 27 to turn
inside it with the aid of threading grooves 54 and to feed threaded plunger 41 to
the left with the aid of threading 55. Thus plunger 41 does not turn. A comparatively
large movement of injection actuator 12 is thereby geared to a much smaller movement
of plunger 41 due to different steepness of threading 54 and threading 55.
[0053] Turning part 27 feeds plunger 41 towards the left and causes ejection of insulin
each time user presses the injection actuator 12 (presuming that the dose injection
means 5 is set to a setting that allows the ejection of insulin). Plunger 41 is returned
to the starting position when the cartridge 40 is replaced. FIG 26 and shows the cone
clutch 53 in its engaged state and FIG 27 shows the clone clutch in its disengaged
state.
[0054] The drive mechanism 13 can be combined with a deactivation means that suitably comprises
at least one sensor for sensing movement or settings of the drive mechanism 13, or
dose setting means 5. In general, sensors that are capable of detecting movement in
a mechanism or the setting of a mechanism are well known. The sensor may be a position
sensor, such as setting mean sensor 17 that senses the position of a part of drive
mechanism 13. In particular the setting mean sensor 17 may sense the position of a
part of a drive mechanism 13 that changes position as the setting of the dose setting
means 5 changes. The part of drive mechanism being sensed by setting mean sensor 17
is preferably a part, the position of which, is determined by the setting of dose
setting means 5. An example of such a part of drive mechanism 13 is member 29 of sleeve
14. The at least one sensor is connected to and arranged to communicate with processing
unit 19.
[0055] Preferably the device has a deactivation means comprising a sensor 17 that can sense
when the dose setting means 5 is set to a setting that permits the drive mechanism
to eject insulin as is described below. The deactivation means which is an important
part of the invention is described further below, as it can be used to switch off
first display 3.
[0056] The device 1 has a user interface that includes one or more displays, buttons for
navigation in menus, and an input device for entering input. The user can obtain information
such as status of the device, blood glucose measurements and the setting of the dose
setting means 5 from at least one display.
[0057] In a preferred embodiment, however, the device 1 has at least two displays: a first
display 3 and a second display 6. In this embodiment the purpose of the second display
6 is mainly to show the setting of the dose setting means 5, thus to show the amount
of insulin to be ejected. In a preferred embodiment the second display 6 only displays
the setting of the dose setting means 5. Other information such as blood glucose measurements,
are shown on the first display 3. In particular, the blood glucose measurements are
shown on the first display 3. In one embodiment the device has one mechanical display
(second display 6) that is capable of showing the amount of insulin to be ejected
by the device and at least one electronic display (first display 3) capable of showing
blood glucose measurements. A mechanical display preferably works without being powered,
for example by electricity. Thus, it can display the dose setting (the amount of insulin
to be ejected) without being powered.
[0058] The first display 3 can be either switched on or switched off. For purposes of this
application, "switched on" means that the first display 3 is capable of showing letters
and numbers, for example a blood glucose measurement, and "switched off" means that
the first display 3 does not shown any letter, digit or symbol that can be confused
with a letter or a digit of a blood glucose measurement. For example, the first display
3 can show lines or circles or other figures that have a low probability for being
mistaken for an actual blood glucose measurement; and still be considered to be switched
off. This indicates to the user that the first display 3 is not broken but merely
that it is currently not displaying any information. For example, if most of the display
shows several rows of dashes (as in FIG. 24) it will considered to be switched off.
Also, for example, if the first display 3 shows several rows of the same digit, for
example the digit "8" (as in FIG. 23) it will also be considered be switched off,
since this will probably not be mistaken for an actual glucose reading or an injection
event. The deactivation means off course also switch off the first display 3 by causing
the processing unit 19 to cut the power to the first display 3. I will then not be
able to show any letter, digit or symbol.
[0059] FIGs 7-9 shows one way of arranging the second display 6 when it is a mechanical
display. Here the second display 6 is arranged on a short side of the device 1. Sleeve
14, which is a part of drive mechanism 13, rotates with the dose setting means 5,
the sleeve 14 having dose markings on the outside. The dose marking may be written
in a spiral-like fashion on outside of sleeve 14 since the sleeve 14 may move when
the dose is set. Sleeve 14 is arranged in the housing 7 such that a section of the
sleeve 14 is visible through a window 15 in the housing 7, as shown in FIGs 7-9. FIG
8 shows the second display 6 seen from above and FIG 9 is an enlargement of FIG 8.
The sleeve 14 is connected to the dosing knob 5 such that the sleeve 14 rotates when
the dosing knob 5 is turned. The selected dose is shown in the window 15 indicated
by an arrow or line 16 on the housing 7. The setting of sleeve 14 determines the amount
of insulin to be ejected by drive mechanism 13 (as it determines how far 52 moves
to the right in FIG 25 nut). The second display 6 may also be such that all the figures
are visible and that the selected number is indicated by a line or an arrow.
[0060] In a preferred embodiment the first display 3 is automatically switched off by a
deactivation means, that may include, for example a position sensor, when the dose
setting means 5 is set to a setting that permits the ejection of insulin. Thus, the
first display 3 is switched off when the dose setting means 5 it set to - for example
- 1.0, 1.5, 2.0, 2.5 and so on, but active or switched on when the dose setting means
5 is set to the at least one setting that does not allow ejection of insulin, such
as 0 (zero) or any other setting that results in that no insulin can be ejected. For
example, besides the setting 0 (zero) there may also be an "off"-setting that also
inactivates the insulin injection means, and that allows the activation of the first
display 3.
[0061] This arrangement directs the attention of the user to the second display 6 which
shows the amount of insulin to be ejected. This reduces the risk that the user sets
the wrong value of the dose setting means 5. For example, there is no risk that the
user looks at the blood glucose measurement and believes that the value of the blood
glucose measurement is the dose to be ejected. Furthermore, it directs the user to
take the next step in the procedure and complete that step and not backtrack to the
previous step (which is the blood glucose measurement step). Thus, the user is guided
towards taking the next step in the procedure.
[0062] A schematic diagram of an example of the deactivation means of the device is shown
in FIG. 10. When the dosing knob 5 is turned, a setting mean sensor 17 which may comprise
a switch 18 sends a signal to a processing unit 19 which switches off the first display
3. The setting mean sensor 17 may for example comprise a spring that causes a member
to push on a turning part of the dose setting mechanism of the drive mechanism 13,
said member moving a switch 18 when the member enters a groove in the turning part
of the dose setting mechanism. The groove is positioned such that the member can enter
the groove only when the dose setting knob 5 is set to the at least one setting that
does not permit ejection of insulin, for example a zero setting.
[0063] Another example of such a setting mean sensor 17 is shown in FIG 6 which shows a
detail of the mechanism of FIG 25. Switch 18 is arranged to detect downward and turning
motion of sleeve 14 which sets the amount of insulin to be ejected. When sleeve 14
is in its most downward position the drive mechanism 13 is set to zero and member
29 of sleeve 14 is in contact with switch 18. The causes the first display 3 to be
switched on. When the user turns the setting knob 5 to set an amount of insulin to
be ejected sleeve 14 turns and moves upward in FIG 6 so that member 29 releases switch
18 which sends a signal to processing unit 19. This signal causes the first display
3 to be switched off.
[0064] The deactivation means can be arranged in many other ways. For example, a semiconductor
accelerometer of the type used in cell phones (smart phones) can be used for sensing
the movement or position of a part of drive mechanism 13.
[0065] The dose setting means of the user-powered drive mechanism of
US 5,593,390,
US 6,221,046 and
WO2009027950 can be easily adapted by a person skilled in the art to be sensed by setting mean
sensor 17 and ejection sensor 33. Those are examples of injection means that can be
used in embodiments of the invention. For example,
US 5,593,390 discloses an injection means with cam lobes that affect a counter that can serve
as the sensor 33.
[0066] The device can be such that the first display 3 is automatically reactivated when
the dose setting means 5 is set to zero. This is a convenient manner for the user
to reactivate the display if necessary, for example if the user has forgot the blood
glucose value and must recheck this. At the same time it forces the user to set the
value of the dose setting means to zero if he or she needs to switch on the first
display. This can be achieved by setting mean sensor 17 sensing that the dose setting
means 5 is set in a position that does not permit the ejection of insulin. As discussed
above, when the user sets the dose setting means 5 to zero, sleeve 14 is its most
downward position in FIG 6. When sleeve 14 is in this position, member 29 is in contact
with switch 18 and this sends a signal to processing unit 19 which causes first display
3 to be switched on.
[0067] In one embodiment the first display 3 is automatically switched on when ejection
of insulin has been completed. With reference to FIG. 25 and FIG 6, the dose setting
means 5 returns to the zero setting during ejection. The switching on of first display
3 can be achieved by setting mean sensor 17 sensing that the dose setting means 5
has returned to the zero setting during ejection. With reference to FIG 6 and FIG
25 sleeve 14 move s downward during ejection of the medicament so that member 29 reaches
switch 18 when actuation means 12 is depressed so that the zero setting is reached.
Thereby, the first display 3 is automatically switched on. This enables the user to
tag the injection event as described below if he or she wishes to do so. Again, the
attention of the user is directed to the next step in the procedure which is using
the first display 3 to log the injection event.
[0068] In one embodiment the first display 3 and second display 6 are not visible at the
same time by the user, such that the user cannot read the first display at the same
time as the second display. An advantage with this arrangement is that the user can
not confuse the values on the two displays. The two displays 3, 6 can, for example,
be geometrically arranged such that it is only possible to see one display at a time.
Alternatively, one display can be of a kind where the digits are only visible from
a certain angle.
[0069] Preferably the displays 3, 6 are on different surfaces on the housing of the device
as shown in FIG 11-12 where the first display 3 is arranged on a first side 20 of
the housing 7 and the second display 6 is arranged on second side 21 of the housing
7. The relationship of the surfaces of the displays 3, 6 can be defined by the angles
of the surfaces of the displays. FIG 12 shows an example of an elongated housing 7
of device 1 seen from the dosing knob 5. The angle α between a line perpendicular
to the surface of the first display 3 and a line that is perpendicular to the surface
of the second display 6 is at least 45°, more preferably 60°, more preferably at least
70°, more preferably at least 80° most preferably at least 90°. "Line perpendicular"
to the surface of display refers to a line that goes through the surface of the display
on the part of the display where the indicated number, letter or symbol is visible.
Typically, this will be the direction from where the user most conveniently observes
the display. When the angle α is 45° or more it is difficult for the user to see both
displays at the same time, which reduces the risk of confusing the two displays and
further directs the attention of the user/patient to one display at a time.
[0070] The device 1 can be equipped with a lancet mechanism 22b with a site for connecting
a replaceable lancet 22 as shown schematically in FIG 1 and FIG13. The lancet 22 is
typically a sharp needle made of surgical grade steel that is able to make a small
puncture in the skin in order to obtain a drop of blood, to be used in blood glucose
measurement. Typically, the lancet 22 is powered by a spring mechanism 22b and ejected
after interaction by the user, for example when the user presses an actuator. Preferably
the lancet 22 and its mechanism 22b is contained in the housing 7 when not in use,
the tip of the lancet 22 being ejected trough a small opening in housing 7 when the
user presses an actuator. The lancet 22 should be ejected with a speed that is sufficiently
for the lancet 22 to puncture the skin and preferably have a stroke depth of 2-3 mm.
Lancet mechanisms are well known in the art. An example of a spring mechanism for
a lancet is disclosed in
WO2009027950. The lancet 22 can also be powered by compressed gas. An advantage for including
a lancet 22 in the device is that there are fewer loose things for the user to keep
track of.
[0071] The housing 7 of the device 1 can be elongated, and roughly have the proportions
as shown in FIG 13 and FIG 4 and 5. Again, the size of the housing 7 is such that
it can conveniently rest in the hand of the user. When the housing 7 is elongated,
the lancet 22 or the site for connecting the lancet 22 is preferably located so that
lancet needle is in one end 23 of the housing 7 and the cartridge housing 10 is preferably
located in the opposite end 24 of the elongated housing 7 so that the needle 42, when
connected, is in the opposite end 24 of the housing 7. This may also apply when the
housing is not elongated. Furthermore, the injection actuator 12 is preferably located
on the same end 23 of the housing 7 as the site for connecting a lancet 22. This has
the advantage that the user, when he or she is positioned to interact with the injection
actuator 12, for example has a finger positioned to depress the injection actuator
12, he or she does not try to inject himself with the lancet 22. This provides additional
safety.
[0072] When the housing 7 is elongated the first display 3 is preferably located in the
middle of elongated shape as shown in FIG 13. When the device 1 comprises a glucose
meter 9, the test strip port 2 is also preferably located in the middle of the elongated
shape as shown in FIG. 13. In this manner the interaction points of the user for glucose
measurement is located in the middle of the housing 7 of device 1. Thus, the middle
of the area of the first display 3 is located approximately 50% from the end of the
housing 7. Approximately 50 % includes 30% to 70%, even more preferably 35% to 65
% and most preferably 40% to 60 % of the distance from the end of the housing. Furthermore,
the second display 6 is preferably located at one end of the housing, preferably the
same end 23 as lancet 22. This further separates the first and second displays 3,
6 and mentally connects each display 3, 6 to a certain way of interacting with the
device, which makes it easier to remember. It also has the advantage that the first
display 3 is clearly visible when the device is held with two hands.
[0073] For further indicating the work flow and allocating the various function to different
parts of the device 1 the angle β between the lancet 22, when the device has a site
for connecting a lancet, and the injection needle, when connected, is preferably about
160°-220°, more preferably 170°-190°, most preferably about 180°. Thus, the lancet
22 and the injection needle 42 are pointing in different directions. Although the
injection needle 42 is not a part of this invention, the direction of the injection
needle 42 is determined by the direction of the cartridge housing 10.
[0074] The test strip port 2 comprises an opening in the housing 7 and an elongated tunnel
which guides the test strip into the glucose meter 9. Suitably the cross section of
the tunnel is somewhat larger than the cross section of a test strip so that the test
strip is guided into the glucose meter 9. When the device has a lancet 22 or a site
for connecting a lancet and glucose meter, the test strip port 2 is preferably arranged
such that the angle γ between the test strip 28, when inserted into the test strip
port 2, and the lancet 22 is from 45° to 135°, more preferably from 80° to 100°, most
preferably about 90°.
[0075] When the device has a glucose meter 9the angle δ between the test strip 28, when
inserted into the test strip port 2, and the injection needle 42 is preferably from
45° to 135°, more preferably from 80° to 100°, most preferably about 90°.
[0076] The device may have an ejection sensor 33 for detecting the amount of insulin that
has been ejected by the device. Ejection sensor 33 is connected to drive mechanism
13 such that it can send a signal to the processing unit 19 that is related or proportional
to the amount of insulin that is ejected by the injection means of the device. An
example of the arrangement of such a sensor is shown in FIG 6 which shows a sensor
which detects rotation of turning part 27 of drive mechanism 13. Turning part 27 which
is a part of drive mechanism 13 has a rim which forms a cogwheel 32 to which cogwheel
31 is connected. Turning of cogwheel 31 is detected by magnetic ejection sensor 33
which is able to send a signal to the processing unit 19. When the user presses actuation
means 12 the turning part 27 turns during ejection of insulin. Turing of turning part
27 causes turning of cogwheels 32 and 31. The turning of the cogwheel 31 and the signal
from the magnetic ejection sensor 33 is proportional to the turning of turning part
27 and thus to the amount of insulin that has been ejected.
[0077] The medical device 1 is equipped with a proximity sensor 35 connected to processing
unit 19. The proximity sensor 35 can sense the presence of a solid object, preferably
the body or a part of the body of a person. This is archived without making contact
with the object. The proximity sensor should be able to detect the body of the user
if the skin is bare or covered by clothing. It should also be able to detect a human
body irrespectively of various skin hues.
[0078] The proximity sensor 35 can be a distance measuring sensor that sends a signal to
the processing unit 19 that can be converted to a distance measurement. Alternatively,
the sensor can be a binary proximity sensor such that it does not actually measure
or quantify the distance but produces a detectable signal change if a solid object
is within a threshold distance.
[0079] Suitably the proximity sensor 35 is arranged to send a detectable change in a signal
when an object is within a threshold distance. Thus, the sensor can be arranged to
send a signal when an object is within the threshold distance and to cease to send
the signal when there is no object within the threshold distance. The sensor may alternatively
be arranged to continuously send a signal if there is no object within the threshold
distance, but to cease to send the signal when there is an object within the threshold
distance. The threshold distance T is defined as shown in FIG 14; from the inside
of the front plate 4 of the cartridge housing 10 and in the direction of the injection
needle 42
[0080] Preferably the proximity sensor 35 reacts to an object with a certain thickness,
such that it does not sense a finger or a small object that passes through the detection
zone, but does react to a larger object such as the leg or the stomach of the user.
Thus, the proximity sensor 35 should be such that it detects the distance from the
medical device 1 to the body or a part of the body of a patient that is suitable to
receive an insulin injection.
[0081] Proximity sensors may be based on heat, IR (infrared light), ultrasound or radio
sensing, where IR is preferred. Sensing can be based on amplitude, frequency, phase
shift or shielding of the object. The desired signal may be derived in change in,
for example, capacity or sensors may comprise a transmitter and a receiver. Preferably
the IR sensor has a transmitter that transmits IR and a receiver that receives IR
that is deflected by a solid object. LEDs are conveniently used for transmitting the
IR wave. Examples of proximity sensors are disclosed in
US 8536507 B2 and
US 8350216 B2.
[0082] As discussed above, the user is instructed to prime the injections means before each
injection.
[0083] The sensor 35 can be used to automatically distinguish priming events from injection
events as shown in FIG 15, FIG 19 and FIGS 20-22. This is based on that the user primes
the injection means in the correct manner, i.e. does not prime the injection means
by injecting into an object, but instead ejects so that the tip of the needle can
be observed, so that the user can observe the ejection of insulin from the tip of
the needle When the device 1, with the aid of the proximity sensor 35 senses that
a solid object 50 is within a certain distance T it is assumed that the ejection event
is an injection event and when there is no object 50 within a certain distance T it
is assumed that the ejection event is a priming event.
[0084] FIG 20 is a schematic view showing device 1 with needle 42 pointed in the direction
of a solid object 50. The proximity sensor 35 with detection zone 51 are also shown.
In this figure the solid object 50 is not within the threshold distance T and the
ejection event is logged as a priming event.
[0085] FIG 21, shows essentially the same as FIG 20 but here, on the other hand, a solid
object 50 (the body of a patient), is within the threshold distance T and the ejection
event is logged as an injection event. The detection zone is not shown in FIG 21 for
sake of clarity.
[0086] Preferably the proximity sensor 35 is arranged to transmit and receive through an
opening in the housing 7. Preferably, proximity sensor 35 is placed close to the tip
of the needle as practically possible, directed to sense in the direction of the tip
of the needle. Sensing by the proximity sensor 35 preferably takes place approximately
in the direction of the needle 42, such that it can detect when an object is in front
of the tip of the needle.
[0087] The signal from the proximity sensor 35 can be used to distinguish between injection
events and priming events as described below. Suitably the signal from the proximity
sensor 35 is received by the processing unit 19 which can use the signal to distinguish
between priming events and injection events.
[0088] Various connections to the processing unit 19 is shown in FIG 17. The device 1 comprises
a processing unit 19 for controlling the device. The processing unit receives data
from glucose meter 9, setting mean sensor 17 (which may comprise switch 18), ejection
sensor 33 and proximity sensor 35. Processing unit 19 also receives input from the
user and controls the first display 3. For example, processing unit 19 may store information
in a database 200 that can be displayed on the first display 3 in the form of an electronic
log. The processing unit 19 may be an integrated circuit, which using today's technology
can have an architecture which is in the order of nanometers, e.g. as used in mobile
phones. Thus, the processing unit 19 does not take up much space in the housing 7.
A memory 38 is also provided to allow the user to store data, for example logging
injections and blood glucose measurements, preferably in the form a database 200.
The processing unit 19 can also be connected through a data port 39 to a computer
for extracting data and for updating any software stored on the device 1. Such a connection
can be for example a USB or a micro USB connection. The data port 39 may also be a
wireless connection such as a Bluetooth or a Wi-Fi connection.
[0089] The processing unit 19 may have an interface for a switch 18 of setting mean sensor
17 that detects when the dose setting means 5 is set to a setting that permits ejection
of insulin.
[0090] Processing unit 19 may also have an interface for ejection sensor 33 which detects
insulin ejections carried out by the insulin injection means.
[0091] The processing unit is powered by a power source such as a battery 34. Battery 34
also powers other components of the device that requires electricity such as the first
display 3 and integrated glucose analyzer 9. The battery 34 can preferably be reached
and replaced through a cover in the housing 7. The connection for charging may be
a USB data port 39. Data port 39 also may also conveniently be used for retrieving
data stored in the memory 38 of the processing unit 19.
[0092] The processing unit 19 is also connected to the first display 3 and to integrated
blood glucose analyzer 9 and to proximity sensor 35.
[0093] The processing unit 19 may further have a manual input device 36 which may for example
be buttons, a mini joy stick, a navigation plate or similar device for inputting data
and for navigating and scrolling in menus shown on first display 3. A clock 37 provides
date and time information and can also serve as a timer for the processing unit 19.
[0094] The processing unit 19 includes a memory 38, such as, for example, a flash memory,
for storing software and data generated by the device 1 and by the user, e.g. the
database 200. The memory 38 does not necessarily have to be enclosed in the device
1 but it can also be accessed through a wireless connection, for example a wireless
network.
[0095] The database 200 can be used to log blood glucose measurements and insulin ejection
events in a log so that the user, or a technician or medical staff can retrieve the
events.
[0096] In a preferred embodiment the device 1 has an integrated electronic log for logging
blood glucose measurements and insulin ejection events. The electronic log is essentially
a database 200 stored in the memory 38 of the processing unit 19 where the database
200 is accessible through the user interface, preferably the first display 3, of the
device in a convenient manner. The glucose measurement events and ejection events
are stored as entries in the database 200. One schematic overview over an example
of database 200 is shown in FIG 16.
[0097] By way of example, the user, a technician or medical staff can access the electronic
log by choosing an appropriate command in the menu by scrolling through the display
using +/buttons and then see a list of blood glucose measurements or ejection events,
or both. Preferably the default is that the events are shown in date order with the
most recent event shown first. Ejection events and glucose measurement events can
be tagged by the user with additional information, that is, additional information
regarding the events may be stored in the database.
[0098] FIG 15, 18 and 19 are flowcharts showing examples of how the processing unit 19 and
sensor 35 operates when the user carries out treatment and logs events according to
the method for logging according to the invention. The steps shown in FIG 15, 18 and
19 are under the control of software programs stored in the memory and executed by
the processing unit in a conventional fashion. Any suitable programming language or
technique can be used to implement the database and the electronic log.
[0099] In its most general form the method for logging injections of a medicament is an
implementation of the method schematically shown in FIG 15. The electronic log comprises
a database 200 which is stored in the memory 38 of processing unit 19. In step 600
an ejection event is stored in the memory of the device 1, the ejection event comprising
information about the amount of ejected medicament and the time and date for this.
During or immediately after the ejection process, the proximity sensor 35 senses if
there is a solid object 50 in the proximity in the direction of the injection needle.
Also in step 600, the processing unit 19 receives a signal from the proximity sensor
35. If there is no solid object in the proximity, for example if a threshold value
for the distance to a solid object is exceeded, a decision is made by processing unit
19 in 601 to tag the ejection event in the memory as a priming event in 602. If there
is a solid object in the proximity, the ejection event is tagged as an injection in
step 603.
[0100] Preferably the method is carried out automatically by the device 1. The determination
in step 601 can be carried out in different manners. In the case when the proximity
sensor 35 sends a signal that can be converted to a distance measurement, the signal
may be processed by the processing unit 19 which has stored the threshold value and
compares the signal with the threshold value and makes the decision in 601. In the
case of a binary proximity sensor, the proximity sensor 35 itself determines if there
is a solid object within the threshold distance and sends a signal regarding this
to the processing unit 19.
[0101] In a preferred embodiment, the threshold distance T can be set in relation to a position
that is fixed in relation to the injection needle, preferably the front plate 4 of
the of cartridge housing 10. The threshold distance T is measured from the inner surface
of the front plate 4 to the longest distance where a solid object, such as a human
body, causes a change in a signal that makes an ejection event to be classified as
a priming event can be seen in FIG 14.
[0102] The user is normally instructed to prime the injection means by holding the injection
means vertically with the needle pointing upward and then ejecting a small amount
of medicament while observing that medicament is ejected from the needle in a normal
fashion, i.e.so that no air is left in the needle and that the needle is not blocked.
Thus, in normal use, it is not likely that priming ejections are made with the needle
close to a solid object.
[0103] Suitably T is chosen so that it accommodates most needle lengths (including the needle
hub) while still being short enough so that no erroneous logging takes place, for
example, if the user holds the device under a lamp while priming. Needles for injecting
insulin are usually between 4 mm and 13 mm long. Thus, if an injection is made when
there is no solid object within 200 mm, 100 mm, 50 mm, 40 mm, 30 mm, 25 mm, 20 mm,
18 mm, or 15 mm from the front plate 4 it is highly likely that the ejection event
is a priming ejection. These distances accommodate most cartridges, length of injection
needles and length of needle hubs.
[0104] The measurement of proximity sensor 35 can preferably be carried out very quickly
(under 1 second) and can be carried out at any time during the ejection, or immediately
after ejection. Sensor measurement should be carried out at least once during ejection,
or immediately after injection, that is within 1 second of completing ejection, more
preferably within 0.5 seconds of completing ejecting, as determined by ejection sensor
33. Alternatively, it is carried out several times during ejection in which case it
may be enough for a solid object to be within the threshold distance once during ejection
as determined by ejection sensor 33 in order for the ejection event to be classified
as an injection event.
[0105] Suitably ejection sensor 33 can be used to determine the time window for when ejection
takes place. Thus, an ejection event may be logged as an injection event only if a
solid object is within the threshold distance during the time when ejection takes
place as determined by ejection sensor 33, or immediately thereafter. Thus, if a solid
object is within the threshold distance only after ejection has ceased as determined
by ejection sensor 33, the ejection event is not logged as an injection event.
[0106] Ejection sensor 33 may activate proximity sensor 35, for example by sending a signal
to proximity sensor 35. Such a signal can be sent via processing unit 19, or directly
from injection sensor 33 to proximity sensor 35.
[0107] Alternatively, proximity sensor 35 may be switched on by setting mean sensor 17 (preferably
via processing unit 19) when setting mean sensor 17 detects that the setting means
5 is set to a setting that allows the ejection of insulin. In this case, the time
window for detecting proximity may be determined by ejection sensor 33 as described
above.
[0108] In the following it is described with reference to FIG 18 and 19 how the user can
use the electronic log to log glucose measurements and medicament ejection events.
[0109] A user initializes a test by introducing a test strip 28 into the test strip port
2. This can be detected by the integrated blood glucose analyzer 9 which then automatically
switches on the device. Alternatively, the user switches on the device manually by
using manual input device 36. The processing unit 19 may then carry out a system check
to see that the device 1 is working properly, and for example check that there is
sufficient batter power to carry out the subsequent steps. Suitably, the first display
3 is then switched on, indicating to the user that the device is ready for a blood
glucose test. Suitably the display 3 at this step displays text that instructs the
user to introduce a blood sample such as "AWAITING BLOOD SAMPLE". The user then takes
a blood sample, suitably by using the lancet 22, and places a drop of blood on the
test strip. If this is not done within a suitable time frame, such as 5 minutes, the
program in the processing unit 19 may shut down the device 1 in order to save battery.
When a blood sample is introduced, the integrated blood glucose analyzer 9 can automatically
detect this and produce a blood glucose measurement. Since it takes time to do this,
the processing unit 19 suitably indicates to the user on the first display 3 that
blood glucose measurement is in process, for example by counting down a timer or showing
the text ANALYZING. Usually, 5 seconds is sufficient to analyze the blood sample.
The device may then display an instruction to withdraw the test strip 28 from the
test strip port 2. The blood glucose measurement is stored in the database 200 in
the memory 38 of the processing unit together with date and time for the analysis,
as a blood glucose measurement event in step 400. Then the blood glucose value is
displayed on the first display 3 in step 401. The user may now be given the opportunity,
in step 402, to store additional information together with the blood glucose measurement
event in the database 200 in step 403. This can include adding a data point that indicates
one of the following: if the user recently has taken a meal, if the user recently
has carried out exercise, or if the user is feeling ill. This procedure is referred
to as "tagging" the blood glucose measurement event. For example, by scrolling in
the menu, the user first selects "TAG" and then one of "MEAL", "EXERCISE" and "ILLNESS".
If the user choses in step 402 not to add a tag, the device 1 can automatically switches
off in step 404 after a certain time of inactivity, for example 10 seconds.
[0110] The blood glucose measurement events and ejection events in the database 200 can
be accessed at any time by the user, technician or medical staff. This can be done,
for example, by starting the device 1 and selecting a command, for example "LOG" in
the menu. The user can read the various blood glucose measurement events as a list
by scrolling through the menu. Suitably, the database 200 can also be accessed through
the data port 39, so that the contents of the database 200 can be transferred to a
PC, tablet computer or other computing device.
[0111] Insulin ejection events can be stored in the database 200 in the following manner.
In step 500 of FIG 19 the processing unit 19 detects an insulin ejection and determines
the amount of insulin that was ejected. This can be achieved by the ejection sensor
33 sending a signal to processing unit 19.
[0112] When the injection means are designed with setting mean sensor 17 the processing
unit 19 may use a signal from setting mean sensor 17 to be ready to receive input
from ejection sensor 33 as follows: When setting mean sensor 17 sends a signal to
the processing unit 19 that the dose setting means is set to a setting that permits
the ejection of insulin, processing unit 19 is set in a state so that it is ready
to receive a signal from sensor 33 and sensor 33 is set in a state where it is ready
to create and send a signal to processing unit 19. Thus, ejection sensor 33 can be
activated by setting mean sensor 17.
[0113] The signal from setting mean sensor 17 may also be used by processing unit 19 to
be ready to receive input from proximity sensor 35 as follows: When setting mean sensor
17 sends a signal to the processing unit 19 that the dose setting means is set to
a setting that permits the ejection of insulin, the processing unit 19 is set in a
state so that it is ready to receive a signal from proximity sensor 35 and proximity
sensor 35 is set in a state where it is ready to create and send a signal to processing
unit 19. Thus, proximity sensor 35 can be activated by setting mean sensor 17.
[0114] Information about the amount of insulin that has been ejected is stored in the memory
38 of the device, preferably in the database 200, as an ejection event together with
date and time for ejection in step 501.
[0115] In step 502 the proximity sensor 35 senses whether ejection takes place in the proximity
of a solid object. The proximity sensor can be configured to continuously measure
proximity during the time of ejection, and the fact that step 502 is after step 500
and 501 in FIG 19 merely reflects that the signal from the proximity sensor 35 can
be processed by the processing unit 19 after the storing of the ejection event (step
501). This can suitably be done once immediately after beginning ejection (as, for
example, determined by ejection sensor 33) or immediately after finishing ejection.
The presence of a solid object during that one time may be sufficient to log the ejection
event as an injection event.
[0116] If the distance to a solid object is larger than the set threshold value T the ejection
event is tagged as a priming event in step 504. If the there is a solid object within
the threshold distance the ejection event is determined to be an injection event and
the ejection event is tagged as such in step 505.
[0117] Information about the ejection event can then be displayed, step 506, on the first
display 3 of the device. Preferably this occurs when ejection is completed as detected
by dose setting sensor 17 or by ejection sensor 33. The user may then be given the
opportunity in 508, to tag the ejection event in step 507 in the same manner as the
glucose measurement event can be tagged. Preferably, the ejection event is only displayed
on the first display 3 after ejection is completed. Tagging is suitably available
within a certain time frame which can be 10 seconds. After that time frame the device
shuts down in step 509 in order to save battery.
[0118] Again, tagging can include one of the following events: if the user recently has
taken a meal, if the user recently has carried out exercise, or if the user is feeling
ill. For example, by scrolling in the menu, the user first selects "TAG" and then
one of "MEAL", "EXERCISE" and "ILLNESS".
[0119] The injection event can be automatically connected in the database 200 to a blood
glucose measurement event in the database if the injection is made within a certain
time of making a blood glucose measurement. That time can be 60 minutes, 30 minutes,
20 minutes, 15 minutes or 10 minutes. Preferably the time is 30 minutes after or before
a blood glucose measuring event. Even more preferably, the time is 30 minutes after
a blood glucose measurement event. This is carried out by storing in the memory 38
information that links or associates the injection event to the blood glucose measurement
event.
[0120] The ejection event in the database 200 can be stored together with information if
whether the ejection was a injection event or a priming event. The electronic log
can be such that ejection events that are tagged as priming events are not accessible
to the user via the user interface on the device 1. For example, they are only accessible
after entering a code or through the data port, or both. This has the advantage that
the user does not usually have access to and does not see the priming events and does
not confuse the injection events in the log with the priming events. The priming events
of the database are still accessible for a medical doctor or nurse that wants to check
up on the compliance of the user, or a technician that performs service on the device.
The injection events in the log are, however, suitably accessible to the user. For
example, the user may view information about these on the first display.
[0121] FIG 16 is a schematic representation of an example of a database 200 containing two
exemplary entries representing insulin ejection events. Event 201 is an example of
a priming event and event 202 is an example of an injection event, which has been
tagged with MEAL by the user because the patient has taken a meal in connection with
the injection. Event 201 is present in the database 200 but may not be visible to
the user through the interface of the device 1.
[0122] The database 200 can be such that ejection events are classified as injection events
by default and storing a tag with the ejection event classifies it as a priming event
as seen in FIG 16. Alternatively, the database 200 can be such that that ejection
events are priming events by default and storing a tag with the ejection event classifies
it as an injection event.
[0123] In an alternative embodiment the method the electronic log takes the length of the
needle into account in a manner shown in FIG 22. In this embodiment an ejection event
is classified as an injection, if, when insulin is ejected, the distance from the
sensor to the tip of the needle (D
1) is larger than the distance from the sensor to an object (D
2) and where D
1-D
2≥ distance A
[0124] In this embodiment, an ejection event is logged as an injection event if the needle
has entered at least A mm into the solid object, i.e. the body of the patient. A shall
be chosen to accommodate the fact that the needle shall enter the body sufficiently
and that also take into account that injection can be done through clothing such as
a loose-knitted sweater. A can for example be, 0.1 mm, 0.5 mm, 1 mm, 5 mm or 10 mm,
depending on the length of the needle. Thus, the length of the needle has to be entered
into and stored in the memory of the processing unit 19 or as hardware.